<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Text Fragments Test</title>
    <script src="/resources/testharness.js"></script>
    <script src="/resources/testharnessreport.js"></script>
    <script src="/resources/testdriver.js"></script>
    <script src="/resources/testdriver-vendor.js"></script>
</head>
<body>
    <!--
    The document performs a same-document navigation, which contains the text fragment 'foo'.
    'foo' is inside of a <a> element. If it were focused, hitting `Enter` would
    directly navigate to its href, which is not intended.
    Instead, it should only have the sequential focus, ie. pressing `Tab` would focus the next
    focusable element.
    -->
    <a href="#" id="link">foo</a>
    <button id="next-button">Next Focusable Element</button>
    <script>
        // Define the test for text fragment focus behavior
        promise_test(async t => {
            const link = document.getElementById('link');
            const nextButton = document.getElementById('next-button');

            const hashChange = new Promise(r => window.addEventListener('hashchange', r, { once: true }));

            // Simulate a same-document load to the text fragment
            location.hash = '#some-hash-to-trigger-hashchange:~:text=foo';

            await hashChange;

            // Assert that the link element does not have focus initially
            assert_not_equals(document.activeElement, link, 'Link element should not have focus initially');

            // Simulate pressing TAB to shift focus to the next element
            await test_driver.send_keys(document.body, '\uE004'); // '\uE004' is the WebDriver key code for TAB

            // Assert that the next focusable element (button) has focus
            assert_equals(document.activeElement, nextButton, 'Next focusable element should have focus after pressing TAB');
        }, 'Text Fragment focus behavior');
    </script>
</body>
</html>
